Doctor Who has been accused of many things during its 50 years on TV - most to do with cheesy special effects - but "thunderingly racist" is probably not one of them.

A group of academics claim the popular British sci-fi show is steeped in attitudes "that continue to subjugate people of colour" and shows contempt for "primitive" people.

In a new book, Doctor Who and Race, they argue that the Timelord is dismissive towards his black companions and question why he is more interested in battling Daleks and Cybermen than fighting slavery.

One even cites the Doctor's love of cricket as proof of the show's prejudices.

Professor Amit Gupta says that Peter Davison's incarnation of the character in the Eighties "portrayed the amateur English cricketer of the late 19th Century when the game was characterised by both racial and class distinctions.

"Cricket also had a role in maintaining the status of British imperialism through the exercise of soft power as it was successfully inculcated by the colonial elites. Davison's cricketing Doctor once again saw the BBC using Who to promote a racial and class nostalgia that had already outlived its validity."

Although the faces on Doctor Who have been predominantly white - to date, there has been no black Doctor and shows in the Seventies had white actors playing Asian parts - more recent producers have tried to champion a more diverse cast.

However, another contributor to the book criticises these attempts, citing the relationship David Tennant's Doctor has with black companion Martha Jones (played by Freema Agyeman).

She says an episode in 2007 had the Doctor speaking dismissively of Martha's fears that she would be sold into slavery as the two characters visited Elizabethan England.

The Doctor tells her to "walk about like you own the place. It works for me."

The author claims the comment "betrays the ignorance of writers about historical racial violence and contemporary white privilege".

Australian academic Lindy Orthia, who compiled the anthology by the team of 23 academics, said: "The biggest elephant in the room is the problem privately nursed by many fans of loving a TV show when it is thunderingly racist."

The BBC responded to criticisms, saying: "Doctor Who has a strong track record of diverse casting among both regular and guest cast. Freema Agyeman became the first black companion and Noel Clarke starred in a major role for five years. Reflecting the diversity of the UK is a duty of the BBC, and casting on Doctor Who is colour-blind. It is always about the best actors for the roles."

Ironically, the first actor to play Doctor Who, William Hartnell, was notoriously racist, homophobic and anti-Semitic.